On 21 July 2026, a member of the Centre’s team was awarded her doctoral degree at the Clean&Circle building. Dr Magdalena Bogdanova holds a bachelor’s degree in Biomanagement and Sustainable Development from Sofia University “St. Kliment Ohridski” and a master’s degree in Tourism Management from New Bulgarian University. During her bachelor’s studies, she participated in an Erasmus+ student mobility programme at Université de Strasbourg.

Her professional training includes management and marketing in the tourism sector, while she has also pursued research in the fields of sustainable development, the circular economy and wastewater treatment biotechnology. In addition, she works in the field of funding through European programmes and has international experience in European Union initiatives. She was enrolled as a part-time doctoral student in the Biotechnology/Wastewater Treatment Biotechnology programme from February 2022 until February of this year.

Magdalena Bogdanova’s academic supervisors were Prof. Yana Topalova, DSc, and Assoc. Prof. Ivaylo Yotinov, PhD, from the Faculty of Biology at Sofia University, both of whom are also members of the Clean&Circle Centre of Competence team. The doctoral candidate’s research focuses on sustainable water management, the application of innovative wastewater treatment technologies and the development of circular solutions for the sustainable development of Black Sea tourism. Magdalena Bogdanova is a co-author of four publications in scientific journals and has participated in a wide range of projects, including two funded through corporate programmes and one carried out in cooperation with China. She has also taken part in seven scientific and business forums.

Her dissertation was entitled “Circular Solutions for the Sustainable Development of Black Sea Tourism, with an Emphasis on the Management of Wastewater Treatment Processes”. Tourist areas place considerable pressure on the environment, as well as on wastewater treatment plants themselves. This creates a risk of micropollutants and increased microbiological loads, highlighting the need for greater technological resilience that can enable the circular management of water resources. Based on an extensive research programme related to the Ravda Wastewater Treatment Plant, the dissertation aimed to identify key problems and interdependencies and, on this basis, propose biotechnological solutions that could be incorporated into circular management models and strengthen the connection between science and the tourism sector.

To address seasonal pressure and the increased volumes of wastewater generated during the peak tourist season, Dr Magdalena Bogdanova and her research team examined two conventional approaches: constructing new wastewater treatment plants or expanding existing facilities. However, these solutions require substantial investment and lengthy design and construction periods and are unable to respond quickly to the growing challenges faced by areas with pronounced seasonal fluctuations.

For this reason, the research focused on biotechnological solutions for intensifying the existing treatment processes at the Ravda Wastewater Treatment Plant. The main emphasis was placed on optimising the performance of activated sludge, improving the efficiency of biological treatment, reducing complex toxicity and applying cold atmospheric plasma as an innovative method for stimulating microbial processes and subsequently detoxifying and disinfecting wastewater.

These approaches create opportunities to achieve higher-quality treated water, improve the protection of coastal ecosystems and expand the possibilities for water reuse in accordance with the principles of the circular economy, which is directly relevant to the sustainable development of tourism.

More than 1,029 analyses were conducted as part of the dissertation research. Based on the results, three conceptual models were developed for managing the technological processes at the Ravda Wastewater Treatment Plant. The first model presents the existing technological scheme, which includes the chemical removal of phosphorus through the application of ferric chloride. The second model proposes a transition to a scheme involving the biological removal of nitrogen and phosphorus (DNBEPR). The third model incorporates cold atmospheric plasma technology through the pretreatment of incoming wastewater to stimulate biological processes, followed by the treatment of the purified water to provide additional detoxification and disinfection. The results demonstrate significant potential for improving water quality and expanding opportunities for its reuse.

Among the original scientific contributions of Dr Magdalena Bogdanova’s dissertation is the introduction of the MPN and MPF indicators for assessing the metabolic potential of microorganisms. For the first time, it was demonstrated that short-term, one-minute plasma treatment of incoming wastewater can stimulate microbial processes and improve the efficiency of biological treatment, while three-minute plasma treatment of wastewater at the treatment plant outlet has the potential to provide additional detoxification and disinfection. For the first time in Bulgaria, the complex relationship between tourist pressure, wastewater treatment efficiency and the possibilities for reusing treated water was examined in the context of the circular economy, and technological solutions for optimising the operation of wastewater treatment plants were proposed. Four scientific articles related to the dissertation research have also been published.

All four members of the academic committee voted unequivocally in favour of awarding Magdalena Bogdanova the educational and scientific degree of Doctor. Each of them congratulated her on the excellent work and highlighted the innovative and original nature of the doctoral candidate’s research.

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